Conventionally, as a bottle formed of a synthetic resin material in a shape of a bottomed tube, as set forth in, for instance, Patent Document 1 below, a bottle having a constitution in which a bottom wall part of a bottom part includes a grounding part that is located at an outer circumferential edge, a standing peripheral wall part that is connected from a bottle radial inner side to the grounding part and extends upward, a movable wall part that protrudes from an upper end of the standing peripheral wall part toward the bottle radial inner side, and a depression peripheral wall part that extends upward from a bottle radial inner end of the movable wall part has been known. In the known constitution, the movable wall part rotates about a portion connected to the standing peripheral wall part so as to cause the depression peripheral wall part to move upward, and thereby a pressure reduced in the bottle is absorbed.